The new and distinct grapevine described and claimed herein originated from a hand-pollinated cross of ‘ES 2-11-4’ (unpatented) and ‘DM P3-54’ (unpatented). ‘DM P3-54’, the male parent, is a blue grape which resulted from a cross of ‘Suelter’ (unpatented) with the German vinifera variety ‘Morio Muskat’ (unpatented), and maintains the flavor of ‘Morio Muscat’ as well as much of the winter hardiness of ‘Suelter’. ‘ES 2-11-4’, the female parent, is a white grape of French and American hybrid parentage with rather large clusters and berries having a pleasing neutral flavor and making a white wine that has been compared to Chenin Blanc. Thus the new variety is a complex hybrid with genes contributed by V. vinifera, V. riparia, and several other species, these having come from the at least three French hybrid varieties in the background of ‘ES 2-11-4’. The cross was made in 1983 near South Haven, Minn., where the seedlings were grown out and evaluated and the new variety selected for additional testing in 1987.
In 1988 the original plant selection was propagated asexually by rooting hardwood cuttings at South Haven, Minn., and a second test planting was established. The new variety was found to root readily from hardwood cuttings and all propagules have been observed to be true to type in that the vegetative and fruit characteristics of the original plant have been maintained. Subsequently, other test plantings were made in Minnesota and at Pierce, Nebr. Nearly two decades of testing has shown considerable winter injury during cold winters at South Haven, Minn., a USDA Plant Hardiness Zone 3 location, but only light to moderate injury in zone 4B locations, similar to the ‘Foch’ French hybrid cultivar (unpatented). Compared to other grape cultivars of Minnesota origin, the new variety appears to be hardier than ‘Swenson Red’ but less hardy than ‘Edelweiss’.
Vines of the new variety have been of moderate to somewhat less than moderate vigor, depending upon the growing location. ‘DM 8313-1’ displays the somewhat trailing growth habit typical of many French hybrid cultivars. It has tested from somewhat below average to somewhat above average in productivity compared to many other cultivars tested in several locations. The new variety is moderately resistant to most common fungus diseases of grapevines. Under the occasionally humid conditions of the Midwest it would seem to require a normal chemical disease control program to protect from downy mildew (Uncinula necator Burr.) which is controllable by the use of available fungicides. The fruit has shown no inclination to split following rains and hangs in good condition for late harvest. Berries adhere well to the fruit pedicel and do not shatter from the clusters during this time.
The new cultivar ripens in early midseason, about with the ‘Foch’ cultivar. Sugar and acid balance is good for winemaking with brix readings around 20 degrees and acid readings around 1%, these readings being considered good for grapes raised in a cool Zone 4 location. The berries are greenish yellow at harvest, weigh about 1.5 grams apiece, and are spherical in shape. Clusters are small medium in size, about 65 grams, cylindrical to conical in shape and moderately well filled but not compact. Clusters are borne two or three per shoot on medium long peduncles that are relatively easy to harvest. Grafted vines or vines grown on fertile soils have produced significantly larger clusters than the averages given here.
The new variety has a fine muscat flavor similar to Vitis vinifera variety ‘Muscat Blanc’ (unpatented), and has produced excellent wines when vinified by both amateur and professional winemakers.